Performance anomaly m1015 vs supermicro aoc-saslp-mv8

serverworks

New Member
Aug 5, 2015
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Strange thing, with Ubuntu server zfs and my 2 supermicro aoc-saslp-mv8 (marvell 6480) with 16 2tb drives attached I was getting about 1050 MB/sec on scrub, same array I upgrade to 2 M1015 (sas2008IT) and my scrub is now 800 MB/sec. System specs Supermicro x10sll-F-O, Pentium G3258, 16GB ECC ram. Any ideas why this would occur?
 

Patrick

Administrator
Staff member
Dec 21, 2010
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That Marvell card is good for a maximum of (PCIe 1 = 250MB/s * 4 lanes) 1GB/s in each direction, not including any overhead. The LSI card is a PCIe 2.0 x8 with an interface bandwidth of (PCIe 2 = 500MB/s * 8 lanes) 4GB/s.

I would be a bit surprised if the older, lower power card was pushing 55% of its theoretical max while the newer higher power controller on a the newer interface is only pushing 10% with the exact same setup and drivers installed. It may well be the case, but seems odd.
 

Stanza

Active Member
Jan 11, 2014
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Is the 1015 running at it's native x8 speed?

or has the PCI-E Slot it's in been clocked down some ?

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